[jacquesm]

I don't know why they would get a patent on something that obvious. They could simply do it without needing a patent.

[jcl]

Moreover, if a company copied them to gain similar legal immunity, who would they sue for patent infringement?

[Retric]

Until the patent troll shows up. While it's slightly cheaper to just disclose the idea, filing a patent helps the patent office avoid granting a patent on the same idea.