The ones I can think of at the.moment are: Seals & Crofts, Crosby Stills Nash & Young, Van Halen, Bonham, Saraya, Nelson. Were there many others and was this a 70s folk / 80s hair metal trend?
Santana. Fleetwood Mac (sorta; one and a half surnames for that one).
Winger, and Dokken.
Danzig. (Granted, Danzig isn’t the name he was born with, but still…)
Megadeth. Named for their first drummer, Frank Megadeth.
And of course Slayer is named after Hans Slayer, their accordionist.
And I shouldn’t need to tell you all about Mr. Anthrax’s band…
Can’t believe I forgot some of those those. But it did remind me that “Slaughter” (feat. Mark Slaughter, for real), is another one.
Emerson Lake & Palmer
There are lots of brothers & sisters, but I don’t think that qualifies
Bon Jovi
Then there were the Beatle brothers, Leif & Click.
Nelson
Speaking of crappy and creepy blond dudes, Hanson.
(Danielle, Este, and Alana) Haim
(Alison) Goldfrapp
(Chris) Daughtry
I guess not (Daryl) Hall & (John) Oates, since their first names are apparently officially part of the band name.
Argent
I’m not sure if Guns ( Tracii Guns) n Roses (Axl Rose) meets the criteria. And I don’t think L.A. Guns (Tracii Guns) does.
Giuffria
Man, is that fun to say.
Montgomery Gentry
Dio, named for singer Ronnie James Dio.
Montrose
Allman Brothers.