Why aren't all hybrid cars "plug-ins"?

Hi,

I am trying to figure out why many hybrid car models cannot be plugged in for battery charging.

Is it technology gap, legal...?

Thank you!

They are harder to make than other cars cuz we have been making the 'non plug in' ones for yearsss. Plus they are a lot more expensive to make which jacks up the consumer price.
Also, hybrid does not mean battery powered. They use other forms of energy than gas, but hyrbids are not battery powered cars

I hope I helped