I've made it a habit to ping and dig my servers before signing in to a new wireless network. Of the hundreds of coffee shops, trains, planes, airports, etc that I've done this at, there has only been one network that blocked/rerouted both ICMP and DNS requests: a university that shared its network security team with a nearby national lab.
However, exploiting these holes on a wireless network is incredibly easy to detect and block for an admin worth their salt. It's quite likely that at least a few of the networks I've been on would start blocking traffic from an unregistered device making tons of DNS requests.
That being said, just pay the few dollars they charge for access. If your time is money, this small fee won't be noticed. If you just want to be able to refresh Reddit/lurk on HN, maybe you should take this opportunity to get away from technology for a few hours (while sitting in an aluminum tube hurdling through the skies).
However, exploiting these holes on a wireless network is incredibly easy to detect and block for an admin worth their salt. It's quite likely that at least a few of the networks I've been on would start blocking traffic from an unregistered device making tons of DNS requests.
That being said, just pay the few dollars they charge for access. If your time is money, this small fee won't be noticed. If you just want to be able to refresh Reddit/lurk on HN, maybe you should take this opportunity to get away from technology for a few hours (while sitting in an aluminum tube hurdling through the skies).