I've never configured an Airport, but I assume there's a web interface for configuration. However, most such access ports do not allow configuration via wireless by default, and instead require changes to be made over a wired connection. It's possible that can be changed, though he then runs the risk (probably small) of losing control of his Airport to any malicious wardriver in range who can guess his password. He also better get familiar with configuring his Airport, because different hotels may require different things, and he won't be able to look things up until he gets online. Some hotels require you to "OK" your way through a bunch of terms of service and indemnity agreements as soon as you connect a device, which can be tricky to do when the device is the WAP rather than a normal client.
Wifi and hotels will never get along well. Way too many firewalls (the real kind, not the kind in your router) and steel doors and just regular thick walls in everyone's building codes for hotels and wifi to get along. You would be wise to remind your relative of this and advise him that wired browsing is likely to be his only option for some time to come, unless he's in an open space like the lobby.
I assumed the relative simply wanted to be able to use his iPad in his room (and maybe out on the lanai if his room has one) without having it tethered to the wall by an ethernet cable. It's a lot of work just for that limited amount of freedom, but people want their iPad experience to match the one they've seen on TV, so...
It is of course possible he's completely unaware of the limitations of WiFi, particularly in commercial construction as you noted, and expects to wander down to breakfast or elsewhere in the hotel with access to "his" connection. But some hotels do offer WiFi in the more public parts of their building (the lobby and conference areas, etc)