The unfortunate truth is, most of these girls operate on herd mentality. They tend to join the work (cosplay, whatever) and follow the lead of a girl they already liked, often completely copying them. Back then we had the Nigri clones (and everyone that copied her got bolt-ons), then we had the Amouranth clones (same deal with the tits), then we had the Belle Delphine clones (again, implants for all clones)...
I can't really tell who Kovicki followed, but there's a good chance her implants come from copying someone she followed. Very few of these girls think for themselves after joining the environment, this isn't even a dig on Kovicki herself, it's on almost the entire industry. And obviously, there's a chance she was one of those free thinkers and she just decided bowling tits sell better (which is unfortunately true, they lose part of the old followers but gain a lot more that can't tell the tits are implants or don't care).