Why can't I send pictures on my Iphone 5 without turning on 3g?

I don't like to keep my 3g on because I use the internet on my phone often, and I'm worried about using all of my data. I live at a university, so I have access to Wi-Fi at all times, and there's usually no need for it. However, I have noticed that whenever I want to send a picture message, I have to turn on 3g for it to work at all, no matter what the quality of the picture. This is not so bad, because I'm in control of it. The worst part is that I also can't receive messages without 3g being on. Because of my situation, I sometimes go for weeks without turning on 3g, and I all of a sudden get a ton of picture messages from weeks ago. This is very frustrating, and I don't understand why this is happening. I'm using Verizon, which I always have, and this has never happened with my other phones. If I can't send or receive pictures without Wi-Fi, I might as well have just kept my 'dumb' phone. Is there any solution to this problem?

It seems that with smart phones you need to have data on to send or receive photos, I don't think there's a solution sorry, however I find photos generally don't use much data to send.

My phone… An Android… Is the same way. I think it is because there's not enough signal strength in Wi-Fi to send pics. The phone's 3G may possibly be more secure, have a stronger signal and use less data than Wi-Fi.