I think it's fine to have one big "shower" for the first baby - often done before baby arrives and as a way for people to help the expectant parents out with small (or large, depending on the guest) gifts.
But, after that I like what's called a "sprinkle" instead of a shower. It's usually used as a meet and greet once baby #2 arrives and people if they want bring small things, diapers, outfits, toys, etc but none of the big necessities. Really more of a way to get all of the visitors out of the way at once (I wish we'd done the shower after baby - the constant stream of people in my house after was stressful!)
We purposely went out and bought all of the "big" stuff before anyone else had the chance to with our first. I knew most of my guests would bring gifts, and gladly so - I am always so happy to give gifts to new parents, or new babies - but I didn't want anyone to feel obligated to make a big purchase or spend too much on us. We chose to have a baby, it's our job to afford that baby. But all the gifts we did receive were very useful and greatly appreciated - and things we will be holding on to so we don't need to buy them again for #2!
I DO think every baby and pregnancy deserves to be celebrated - but the intentions between a first shower and subsequent to-do's need to be very different.