It's a very old and rather tired joke, but it wasn't all that long ago that music contracts specified "4 musicians and a drummer". It's not really a case of drummers not getting the same amount of respect as other musicians. It's simply that many non-drummers don't realise that playing drums well requires every bit as much training and knowledge as any other instrument.
There's a lovely video on Youtube in which Travis Barker is warming up before
a gig. In case you didn't know, Travis is highly trained, highly skilled and
highly disciplined. The fellow there with him -- also a band member -- remarks
in a disbelieving tone, "You mean you actually practice your instrument?" Oh my.
There are a lot of drummers who are not interested in studying or practicing
... or even in improving. But that's not peculiar to drummers. A lot of
musicians don't seem to put in much effort after learning those first few chords
and songs. There have even been music movements that eschewed any sort of
education or training. It's a personal choice, but consider the long-term
consequences of that choice.
The less you know about your instrument and about music, the less valuable
you are as a player. That means the better gigs will always go to someone else.
There's also a limitation on opportunities. Perhaps you enjoy teaching. Well you
won't attract many students if you can't read and don't know the basics, or if
you don't understand how to get from one level of playing to the next.
I certainly want more opportunities rather than fewer. But for me the real
bottom line is how I feel about my playing and the quality of the work that I
do. I don't like half efforts, and I tend to put a lot of energy and care into
everything I do. Drums are no different. And if I want to do a high quality job
-- for me if not for any other reason -- then I owe it to myself to continually
hone my craft.
And the best part? It feels great to cover new ground and develop new
competency. And the positive feedback is pretty good too.