Horro/Sci-Fi 80's/90's movie: your help needed


Hello everyone,
I need your help to identify the movie with the following description:

it's a Horror-sci-fi movie from late 1980's or early 1990's.
Made in the USA
In color, no B/W

Scene at the supermarket: a mother and her very young daughter (4-5 yo) are at the supermarket's register, such little girl gets lost.
Soon an old and strange man (I GUESS with a hat, but not sure), finds her and helps her by consigning her to her mother.
Just after the mother and child walk away the little girl turns around to look at the old man who is now standing still (I GUESS near an escalator) and she gets scared as she realizes that the old man is a ghost as people in the mall are walking thru him without noticing him.

Further scene: 1 or 2 people take the same taxi (or a lift from a simple driver), the driver apparently is a human but shortly after he takes of his face-mask revealing a blackface with red light-powered eyes. The taxi than takes off for a flight (I GUESS to outer space).

Thank you very much in advance for your help

The doors of wisdom are never shut. - 'Socrates'
The second descriptions sounds a bit like The Last Starfighter
Did you know that Blue Harvest was the fake working title to hide the 1982 production of Star Wars Episode VI: Return of the Jedi.

That elusive hide-and-seek cow is at it again
The first reads like it might be from Poltergeist II.
"My Dionne Warwick understanding of your dream indicates that you are ambivalent on how you want life to eventually screw you." - Joel

"Ever try to forcibly pin down a house cat? It's not easy." - Captain Steel

"I just can't get pass sticking a finger up a dog's butt." - John Dumbear

That's the movie!!!! Thank you!
I owe you a drink!
The first reads like it might be from Poltergeist II.