ORD (AA) is quite notorious for this if the flight arrives early or very late. All the gates seem utilized to the max at certain times of day. After landing 2 hours late from SYR, we sat 25 minutes waiting for a gate to open up, and almost everyone missed connections in the process.

I once sat on DL at COS for 30 minutes, because my flight from SLC was late, the flight from DFW just landed, and there was only one gate. Was quite annoying to see other vacant gates that we couldn't use.

I also have had this problem with DL at SYR, since they have three gates, but only two jetways. But now that they have cut several flights, they have very ample gate space.