Many of the higher end sights and even some of the more economical ones, come with a light to help brighten things up when the lighting isn’t perfect. I think it’s a necessity if your state allows their use. I find myself practicing in the most perfect lighting and weather conditions and sometimes forget that things aren’t always perfect. It never hurts to be prepared for anything, when it comes to hunting situations.
Obviously, you will want to check the regulations of the state that you plan on hunting and it is your responsibility to know the rules. From what I have seen, several states allow “illuminated sights” BUT, do not allow anything that projects light toward a target. Some states don’t allow lighted anything, so make sure to do some research!
The first few minutes and the last few minutes of legal hunting hours can present more than just vision problems. If you are hunting, deep in the woods with a heavy canopy, it gets dark a little quicker than it does on a field edge. Having a sight light can take even the dimmest of pins and turn them into a glowing beacon. Being able to see you pins & housing are a must for accuracy. Hunting out of a ground blind or a box blind can also have a restriction on your available light if you haven’t prepared or practiced in the exact situation.
Do your homework on what your states allow and be prepared for anything. If your hunting sight doesn’t have a light, it is a relatively minor investment that could pay big dividends in the right situation.