it's a metaphor for not being afraid to get dirty and to remember to work hard. Ugh! Kids these days!
R1 made a good suggestion.
I wish someone gave me a free wheelbarrow so I didn't have to carry heavy bags of dirt and mulch from my car/garage to the yard every spring.
Very good for disposing of dead bodies.
They are really handy for lots of things. I even use it for big loads of groceries, from garage to house.
Unless you live in an apartment, they really are very handy to have available for use. And, it is a hoot he gave it to you. Laugh it off and use it. You'll thank grandpa once spring yardwork begins (again, assuming you have a yard to maintain).
You know that so much depends on a red wheel barrow...