Of course they did. It's like the Jurassic Park thing. The first film you have a long buildup to reveal the dinos, but by the 3rd film there's no point anymore. People know what they look like, so just get them going already.
That's why the first film in a series is often the best, althoguh with Aliens Cameron turned the franchise on its head and did NOT make a simple sequel that repeated the formula, leading to a situation where some people like the 2nd more than the first even.
On the flip side, drawing out the reveal is no guarantee of success. Look at 98's Godzilla by Emmerich. They didn't show the thing fully (lots of close ups of parts of it and glimpses before) until near the end, but it didn't make the film better.