Hello,

Can anyone tell me what is the difference between grout (or adhesive)
for floor tiles and grout (or adhesive) for wall tiles?

I would have thought that grout (or combined grout and adhesive) for
walls and floors would be the same thing and could be used
horizontally or vertically?

I can see that adhesives may have differences as wall adhesive will
have to withstand gravity whereas floor adhesive will not, and floor
adhesive on wooden floors has to be flexible which may not apply to
wall adhesive.

Why do I need to buy two products to do the same job?

Thanks.