if you just want to practice noodling there are plenty of inexpensive options. cell phone drum machines like Electrum & RD3 are dirt cheap. many sample & loop libraries are free & there are many cheap/free audio apps which are more versatile than most classic drum machines if you just want to play along with loops & generic beats.
if you really want to get into programming your own beats, drum parts, fills, sounds, songs, ect. I think that's when you see some value in getting a drum machine. i picked up an Octatrack & it's an amazing sample based drum machine but way overkill if you just want a beat to practice with. Ableton on a laptop with something like a Novation Launchpad is another way to trigger similar results but that's got a bit of a learning curve as well, especially if you don't really incorporate electronics in the band.