I know you said "...I am limited in the opportunities I have to make friends with other members outside of my ward...", if this is the only concern or reason you are offended, then feel free to send me your contact information. We live pretty close and I would be glad to get you in touch with a couple people I know who attend the SA Wards. They will get you in the loop of all the activities in the area.
If you are simply offended by the concept, then there are numerous logical reasons for separating based on large age ranges.
1) Population control: So, in the USA there are plenty of members. Within a 25 mile range, we have four or five YSA Wards, each with 300+ members. If those same Wards were to be flooded by older guys, looking for those fancy young gals then these Wards would be over populated, and may even result in the other SA Wards being unbalanced (e.g., lots of women, few men). - Note, we actually do have 31-46, and then 47+, or something along those lines.
2) Common ground: Even the 18 - 21 year old members will rarely have high interest in the 28-30 year old members. The 18 - 21 may still be considering a mission, may be in college, or trying to figure out life while living with Mom and Dad. On the other hand, most 28+ are past all of that, and certainly most 31+ are. This is a very lengthy section, and can even get into maturity levels, common association of friends of the same age, etc.
3) Typical attraction: Typically someone is not attracted to someone over ten years of age, let alone twelve (e.g., an 18 year old dating a 30 year old). I would be willing to guess that 90% of the time, an 18 year old girl would not want to date someone that is much older than 30, and probably at least 95% of the time not willing to date someone who is 36 or older (i.e., twice their age).
Right, so you feel restricted, yes? If you are looking to date someone that is younger than you, but feel restricted due to age, then try out the Institute meetings; class availability contingent. If you are not interested in dating someone under 30, but are merely offended by the concept of age separation, then I'd love to hear your refute to the above being sound logic of just three examples. Certainly I understand there are exceptions to the above three reasons, and to the rest of the reasons, but you have to look out for the interest of the many. In fact, I'm willing to believe that there is statistical information which went into selecting the existing age ranges.
I could estimate a few numbers and use regression analysis to visually display a concept of how more marriages most likely occur through the existing design than opening up all single wards to all ages.
Okay, you want to hear my refute to your points:
1. - Not a valid argument because singles wards are currently set to serve small segments of the singles population. If you eliminate the age restriction what would happen? The existing age segregated wards would readjust their populations to serve those who lived closest to them, so we could reduce our carbon footprint as a church somewhat. It's interesting that you imagine the wards would be flooded with older guys. If there was no age boundary singles of all ages and both genders would interact in the ward, just as they do in family wards, with the exception of everyone being single, and so finding the extra support those who are single need in the church. Your comment about wards being flooded by old guys seeking young women displays your personal prejudices.
2. -I agree that 18 to 24 year old's should have some exclusive activities to attend, because that is a transitional time for those moving from childhood into adulthood and there are many issues unique to them, such as missions and college, starting a new independent life. However, even they should not be prevented from attending the adult activities sponsored by the church.
3. - The very terms you used in this statement support what I have said. Typical is not all. 90% is not 100% Rarely is not never. When the policies and programs of the church marginalize people who are not the majority, that is fostering prejudice. If the church simply encouraged and persuaded people to focus their associations on those of their age peer group I would not have a thing to say, but it is not encouragement and persuasion that the church is using, it is compulsion by mandatory exclusion.
Opening singles wards and activities to singles of all ages would foster understanding and offer opportunities for growth and service that currently do not exist. I do not think that the marital statistics would change substantially, but they would change. More importantly friendships would develop, bonds would form across the current generational gaps, and the smooth flow of experience based wisdom that used to pass from generation to generation would return.