I have a number of steel toed shoes from work but found they didn't work well on the field. Already noted is the weight and comfort factor but in addition is that some of them will cut into your foot when you are constantly kneeling or crawling through the terrain. If you are playing in a field that is wet or has swamp area, these boots typically don't dry very fast either and are very unpleasant to continue playing in after they soak up water.
If cost is a concern, try out some surplus stores that sell boots and get a feel for what works at a reduced cost. Then invest in a really good pair of boots that suit the field you most likely will be playing.