What about the streak when you're on holiday?
First week of september, I'm going to France, probably no internet, so no Duolingo. So I guess I lose all the ... day streak? Isn't there any way to avoid this? :-(
Wouldn't being able to freeze a streak for a week make a streak of a hundred days a lot less impressive? ;)
Only for one day, if you are without internet for more than one day then you have to say bye bye to your streak.
But there is very often ways of getting on the internet. If you have a smart phone or tablet you can often find free broadband in many places as long as your not in a remote region. For example MacDonalds have free wifi in most of their outlets (other burgers are available of course :-)
Unless if you're going to very remote areas, you'll probably find Wi-fi (if you have a smartphone or some other portable gadget). All you have to do to retain your streak is get one XP, so the moment you get a signal, do one of the basic exercises or practice. Just in case, buy a streak freeze from the lingot store. It will keep you safe for one full day of inactivity.
EDIT: If you're staying at a hotel, they'll probably have Wi-fi (But you may have to pay for it).
If you can, try to obtain an app called wificafe which lists lots of free wifi hotspots in hundreds of countries round the world.
I have an iPhone so not sure if it is available for Android but if it is, I can definitely recommend it. It costs about $2 but could save your streak.