I agree.. You really don't "Need" a skimmer. It does help, but water changes will do the job, even though you may want to increase your interval for them if you decide to omit the skimmer.Won't tolerate microbubbles, so either I find one that doesn't do it, find a good air stone supplier so I stop getting duds, or I'll simply go without a skimmer. Small enough tank water changes would suffice if I really wanted.
As for "duds" I don't think that is the problem. Most tanks generate algae fairly quickly. My 55g needs the glass cleaned almost daily, every other day for sure. Same thing with the air stones.
I would get 4 or 5 of them and change them every day or 2, at the end of the week, scrub them clean and there you go.. Similar to what I do with filter socks.. I have enough to last me a month.. once I get to the last one, I dump them in the washer and then I have a fresh supply for another month