The main reason for multiple strips is wood craft basics.
You make a coffee table 12 inches wide,out of 1 piece of wood that piece of wood can :
a: cup with the grain
b: warp in its length
Now take that same piece of wood cut it in half glue together with the grain pattern in opposite directions.
Now the grain of the wood is working for you.They will oppose each other and help keep its original shape.
now take multiple lamination's. same as above but many times.
Nowadays tho supply and demand of certain materials do lead to buying smaller pieces of wood and having no choice in quantity or size.
Any time you laminate wood it is always better to use multiple lamination's compared to a single piece of wood.
This of course refers to solid stock not plywood's.
Also edge grain lumber will give better flex and strength in its length than Flat sawed lumber will.
just my 2 cents worth