Some Cafes block Bitcoin
Wait, what? Which cafeterias try to block Bitcoin? Also, what do you mean they "block" Bitcoin? There is no central server to prohibit access to. Did you perhaps mean bitcoin.org?
I'd advice you to do everything through Tor. The last thing you want, especially if the cafeteria is bitcoin-unfriendly, is to have some merchant suing you for whatever. With Tor the Internet provider, right as well as the router admin, know absolutely nothing. Without it, it's trivial to notice someone's syncing the Bitcoin network.
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They block port 8333. Or a lot of times it's the other way, they only allow traffic on ports 80 (http) and 443 (https) and everything else is blocked. They may allow certain mail RECEIVING ports (110,143,993,995) and perhaps 587 for authenticated mail send but that's it. It's free, but they don't want to deal with the hassle of people doing anything other then browsing the web. So it's all blocked. I do that for a lot of my customers who want to offer public Wi-Fi. It really is more of free web browsing, for anything else get your own internet.
Depending on the equipment you use and the amount of configuration you want to put into it you can even block TOR to a certain extent.
<shrug>
Probably does not matter since there are enough places that don't block things.
-Dave