I've never seen an ad using Chrome on my Nexus 5.
As for iMessage, your friends and family don't need to get an additional app, they can just send you a text, I don't know anyone who has a plan that doesn't offer unlimited texting.
I even moved out of the states for work and use TextNow to text friends and family and none of them have complained.
yes, they can just send a text, but its not as seamless. You can see if someone is typing so you dont reply to them too fast and mess up the conversation flow. You can send full resolution photos and videos (biggest plus to me). Its even faster at sending and receiving messages 90% of the time. It makes regular texting feel archaic. Its something a person really has to use for a while and experience, then go without, to appreciate it.
Can people just download Kik, Whatsapp, etc? Sure, but they aren't going to because that then makes things a hassle of using more than one messaging app just because one person you know prefers it. I have many different ones I'll happily use, but the general (non-tech nerd) public isn't as aware.