This may sound selfish to some, as I know people who say, "they ought to appreciate that everyone is buying them gifts". Yes, parents-to-be understand this very well. Nobody has to throw them a baby shower, and nobody has to buy them big, fancy, expensive presents. However, the parents will probably use these gifts for their current baby and the ones after that. One thing to note is that if the parents-to-be pick out almost ALL gender neutral items, then do not buy them anything specifically for a boy or a girl (unless its clothes, sheets or toys and they already know what they are having) since they obviously want everything gender neutral for a reason. I did this with my registry. I registered for gender neutral onesies, travel system, swing, playpen, etc. Although I knew I was going to have a girl, I wanted gender neutral in case I had a boy later on. Guess what? Almost 3 years later, I had a boy; therefore, all of the stuff still came in handy. I did not have to buy anything new except for clothes, sheets and nursery decor.
One exception to straying from the registry for larger items is if something is discontinued or no longer in stock. Then, you have free range to pick something out on your own. This happened to me. I registered for a particular swing that was discontinued before my baby shower, so my aunt picked a different swing out for me. She did a great job and I was grateful that she still got me a swing eventhough they did not have the one that I originally wanted.
The bottom line is: You can get creative, just not with the larger, more important items. Trust me, pregnant ladies are hormonal and you do not want to upset one and ruin her baby shower. That is something she will NEVER forget.