I've been thinking about building a small tool that would make it easier for me to compare different options and improve the search functionality different loyalty program websites offer Basically something like Point.me or Awardfares, just slightly different.
Does anyone know what the legal situation for this is? I guess most websites probably explicitly disallow screen scraping, or invoking their APIs externally?
(There are some exceptions like SAS Eurobonus - they seem to be cool with external API calls, as long as you don't make money off your tool.)
Also I'd like to host this on a server, so this would be different from KVSTool, which does the screen scraping on the client.

If it's useful for me, I'd of course also be open for sharing the tool with others. But I'm scared of being sued for that.
How can those websites operate legally? .