@dukkure - here are your answers (based on my limited knowledge)
1) TPS will give them the legal documents to work for at least 18 months. So, for at least 18 months, they won't have to worry about being caught and deported (peace of mind for even 18 months is a big deal to a lot of people).
2) Going back knowing you have 0% chance of returning is different from going back knowing you have a decent chance of being able to come back (yes, they might be denied entry even with travel document through TPS, but they might be allowed back as well...it's all about HOPE and POSSIBILITY)
3) Again, it's about lowering your risk. Yes, the risk of being denied entry is always there but TPS will lower the risk a little bit because they will have received travel authorization in advance. When it comes to being able to come back to the US, even lowering your risk by 1% gives people peace of mind. It seems you are underestimating the power of travel document obtained through TPS. Yes, it doesn't guaranty re-entry, but it improves your chances by quite a bit.
4) Just like Asylum, TPS is a humanitarian measure intended to not force people back to their home country where they are unsafe. It's not solely about helping earthquake victims in the traditional sense. The US government prides itself in it's ability to help the helpless. TPS is designed so that people who are legally or illegally present in the US aren't forced (forcefully by USCIS or willingly due to expiration of non immigrant visa) to return to a country facing natural disaster (among other things).
Does this clarify things? Any follow up questions?
