A good rule of thumb is as follows: only connect using machines you own or have sole use of and which are connecting securely through networks you can absolutely trust. Usually this means at home or possibly at work depending upon the network infrastructure.
A hotel network is not one you can trust and therefore I would be wary. If you have phone banking that would be a better option.
Assuming you are using your own laptop/phone/tablet then your banks security should be adequate enough that it won't make much difference whether you log on in a hotel or at home. The main encryption that makes you secure is between your browser and the bank's server, it doesn't rely on the hotel's wi-fi encryption etc.
But don't use a computer that belongs to the hotel or someone else.
No security is 100%, but there isn't much difference between using your wi-fi at home and a hotel's wi-fi elsewhere.
The main danger with hotel wi-fi is knowing that the network that you are connecting to does actually belong to the hotel. It's not difficult to set up a spoof connection that can look like a trustworthy network but is anything but.
It's a risk. It might be a small one, but it's a risk nonetheless.
Internet security is based on the assumption that it is always possible for there to be a bad guy between you and your bank. So being in a hotel or connecting to a fake hotel connection isn't necessarily a problem. I think there's just three things to consider:-
1: that you're using a secure machine, ie. your own phone or computer 2: that the connection is encrypted i.e. padlock 3: that you're talking to who you think you are, i.e. click on the padlock and see what name comes up.