definitely gimmicky, but the barrier to entry is so low (opening an app) that it's worth for me...who knows, you might hit the 1 btc.. xD
I've stacked over 200k sats on spins in the span of ~1.5 years, not daily usage but pretty consistently. Not nearly using the app to its potential, only used the card to pay for things probably 5-10 times.
Not much, but i think well worth the minimal effort in a decade or so