Ok, so much nonsense in the OP, but let's bite a little bit.
It is quite possible, based on mental health issues alone, to score 2 points in one or more categories on the pip application, enough to qualify for the basic rate. I know people who have scored 4 points in more than one category for solely mental health issues. These people are unwell and need support.
Executive disfunction and reliance on other people is a big part of many mental health issues. People who recieve pip for mental health problems are not saying they need someone with them to go out. In one case I know of, the claimant is totally incapable of going out without support (agoraphobia/social anxiety/general anxiety diagnosis). Another claimant I know recieves pip because without ongoing support he will not eat, or sleep, or leave the house, and his pip funds some of that support. Long term reliance on some types of medication for mental health issues can also cause executive function issues, memory issues etc.
People who get pip are also allowed to work, and for many pip recipients it is the thing that allows them to fund the adjustments they need to be able to work.
And quite frankly I don't know anyone who is getting PIP and DLA, and getting thousands. Because you can't. Pip is for those over 16. DLA is for children under 16. No one is claiming both unless it is both for themselves and the child they are caring for. To suggest that someone might be claiming both and making thousands is just nonsense designed to wind people into a self righteous froth. Anyone who is claiming Pip, or DLA (especially DLA I suspect) would exchange every penny like a shot in exchange for being fit well and capable of leading a relatively normal life.
The nasty sneering jealousy of people who seem hell bent on kicking the most vulnerable in society is truly vile on here at the moment.