When I first started collecting LPs years and years ago, wasn't too into 7". But as time goes on, you find one, then another, etc. etc.
Stones Throw used to do the Fan Club 45s which were cool.
Daptone still pumps out 45s on the regular. I actually own them all except 2 - so that's almost 100 from one label alone!
I have a good mix of all genres on 45.
As mentioned, a way to find some really unique tracks.