So the real problem I envision is post gel imaging.

For DNA: Are the straws UV transparent? Can you get straws that are?

For proteins: There is no easy way to get the whole strip of gel out of the straw is there? It would be hard to further stain the protein. Maybe if you placed the straw horizontally in a tray and filled the tray so that only half of the straw was filled with gel horizontally. That way you could just chuck the straw in coomasie and stain your protein or cut the straw lengthwise and transfer the protein on to nitrocellulose or PVDF.