Large file size

I am exporting my cdr files to AI or EPS so the local sign shop that doesn't use CorelDraw can print them. The problem is, the files are huge after exporting them. Am I doing something wrong or is this normal. I hope I am doing something wrong and can reduce the file size. Currently the files are much to large send using conventional email. The Corel file is 4.84 MB. After exporting to AI the file is 858,348 KB.

I have had this problem on other files as well.

Shawn