Is a self charging hybrid really much lighter than a PHEV? unless I’m mistaken, the only difference is the (lack of) charge port and maybe an electric module or two. self charging hybrids are lighter probably because they have much smaller batteries, which means worse economy.
On the Tucson, the difference in battery size alone between the self charging and plug-in hybrid adds 10% to the entire weight of the vehicle. If you never charge it, that extra weight is a liability that will cost you at the fuel pump. Keep in mind that a PHEV is more expensive to start with, so getting one with the intention of never charging it would be a bad move IMHO.