There are levels of understanding. Infinity is a concept that can be applied in a number of different areas. In numbers, we think of the idea of some quantity growing without bound. (OTOH, you can have things that are infinite, but bounded.) That's one use of the concept.

Cost analysts (operations research) types often solve optimization problems in numerous dimensions, none of them spatial. Do you have to actually visualize something to have an understanding of it, or is it sufficient to understand the consequences of the thing - how it might be used?