The "lesbians" you describe (Miller Lite Twins, etc) are about as lesbian as I am short, ugly, & white. Believe me, I am NONE of those. And, beauty (or "hotness") is in the eye of the beholder. Make sure you don't get too close to your fantasy lesbian or move her too close to heat, or the illusion will fade away.
The reasons are simple as why men like yourself are fascinated by these fake lesbians:
1.Men love women.
2. Women are sexy & sensual.
3..Any man thinks 2 or more women are better than 1.
4.Seeing 2 or more women is hot, because men think that after they play with their female friends, they'll want a "real" man.
5.Women together is not a threat to masculinity like men together.
6. Marketers & the porn industry know 1-5 above, & cash in on it.
Pretty simple. Men are easy, & the illusion of 2 or more women together is enough to get them to pay to watch it or buy a product being advertised by it.
The taboos of women hooking up with each other for man's attention is not really a social taboo to the women involved because they aren't lesbians. If you want an artifical, plastic woman with all the eye catching (unreal) attachments, you go right ahead. The real hot lesbians are at home with each other & have no time for silly games. Nor, would they want to put on a show for you.
There IS a negative stigma for real lesbians who express PDAs & get harrassed by men who think their affection for each other is just a show for the men, NOT the love they have for their gf.
I know. My wife & I have BTDT. It gets annoying.