Personally I would keep getting up and feeding him as long as he is eating a good amount. Who are we to know when they are really hungry or not? As you stated, he could be going through a growth spurt, or he may just not be getting enough calories during the day and has to make up for them somehow. I personally do not believe in cry it out, I have three children, 5, 3, and 1, and none of them have ever (and will never) cry themselves to sleep. No offence to those that have done it or believe in it, but I just think it is mean. I hate to hear my children cry and will not make them so that I can get a little more sleep. If you don't want to do cry it out, check out the book "The No-Cry Sleep Solution". It worked for my kids, and as long as you are consistent with it, it will work. You may not get the results those that do cry it out claim to get, having them sleep all night within a week, but you just have to ask yourself how important that is. Is it worth having your baby cry for an hour? Or can you handle putting more work into it, getting the same results in a longer time, but not having to make your baby cry?
Like I said, I have three children, so believe me, I have been in your shoes!! I know how hard it is to get up every night, my 1 year old is still getting up once most nights, and yes, she does still get a bottle when she does. Just know that this is a very short time in your life. It doesn't seem like it now, but when your son is 3 or 4, you'll look back at his babyhood and you'll be shocked at how fast it went by. So why not give him those middle of the night cuddles now, while you still can. Someday he won't want you as much as he does now.
Another thing I've learned is that once you become a parent, you will never not be tired again. lol! Once you are out of the newborn and infant stage, you'll have a toddler that has to get up to go potty or a drink of water. Then you'll have a child that wakes up sick or from having a bad dream (those go for the toddler too!), then you'll have a teenager that you are up worrying about because they are out with friends, or they aren't doing well in school, etc.
He will sleep again all night, I promise, just let him do it in his own time and you'll all be happier.