In about 10 to 15 years, the number of those "returning" will dwindle dramatically since I do not think many started in the 80's then stopped and later to return.
Turning to eBay to fill in many of the early holes on your album pages
can be a productive endeavor, but approach it with a skeptical attitude. Hundreds of successful (buying) transactions for me came with a few early scars.
I'm curious about e-bay as I've been buying quite a few stamps there lately. Do you mean you ended up with fakes? I've seen people mention that that's not unusual in some of the earlier, more valuable US stamps. I've not gotten into that area as I'm still getting common, inexpensive issues, mostly MNH US year sets from the '30s thru the '60s, along with some special sets like Famous Americans.
In one set I got a couple damaged stamps and the seller promptly sent replacements. I've been very impressed thus far. The quality has been solid and the prices a pleasant surprise. Though I see the fairly inexpensive year sets stop at 1926, so I'll run out of those before long. At what point would I need to really get concerned about fakes?