Metaforical goggles, believed to be "worn" due to imbibing to much alcohol. Specifically, the enhanced visual appeal of women who would be considered fugly when sober.
"Sure I can see she's a double bagger now, but I had them beergoggles on last night."
When somebody has a few drinks and suddenly think they know everything. People wearing their Beer Googles are usually compelled by an irresistable urge to share their wealth of knowlegde with anybody who will listen.
Thats not true, pay no attention to him, he is wearing his beer googles.