I spent many years in an originals band, just playing our own stuff, jamming ideas, doing occasional gigs when we could get them and it was great, we were musical puritans maintaining our credibility and integrity in out own little ivory tower. Gigs were scarce, unless we wanted to do flyer deals on a tuesday night (which wore very thin extremely quickly)
so a while ago we decided to switch to about 90% covers in order to get pub gigs, maybe a bit of cash in our back pockets and have a laugh.
I found the process of learning batches of other peoples songs an enriching experience, the opportunity to see how some other players might approach a song, how different rhythm sections interact etc etc etc. I do practice scales, hanon etc, and I still practice bach, but playing other peoples basslines is also a rewarding part of playing that you can learn from.