With the support in 2018 sp01 to import all decal mapping types (not just planar) from SW, we did have to make some changes to break out additional parts for the SW entities that decals are mapped to...just like appearances do.
That said, you're screenshot is showing some extreme example of breaking out parts, based on what looks to me like rather simplistic geometry and decal work. Would it be possible to send the example SW file my way to take a look (with decal image source files)... you can send me a PM.
My guess is that your decal, in SW, is mapped up over the face that has the extruded lettering (ie probably 100's or even 1000's of faces on the lettering). But the decal image itself seems to actually be confined to the indented cylindrical face in the middle. How did you apply the decal in SW? Where is it applied to (is applied to a face or the whole body or part?). Again, if you're able to privately share the model, I can have a look and likely answer most of these questions myself.
I got a chance to look at Shad's model. While we should certainly look to improve this type of case if possible, it is technically working as intended. To get the most desirable transfer in this case, requires using some "best practices" for mapping decals in SOLIDWORKS.
Let me explain...
As I said, in support of importing all SOLIDWORKS decal mapping types in 2018_sp01 (along with the fix to no longer have decals being offset and casting self shadows), we do in fact need to break out additional parts for all faces where a decal is mapped.
What this means, is that if you apply your decal in SOLIDWORKS to anything other than a face (ie feature/body/part or assembly component in Shad's specific case), the faces that belong to said feature/body/part will still be broken out as separate parts in Visualize, even if the decal doesn't cross the boundaries of said faces. When you choose to map a decal to a body, for example, sure you may adjust it so that you only see it intersecting what appears to be a single face, but technically the decal's projection is the entire body...and all its faces.
See the attached images for a simplified example showing how import results differ based on what the decal is mapped to in SOLIDWORKS
As a general rule of thumb, a "best practice" is to try to always apply decals, at the part level, onto faces only. In Shad's case, the main label on the bottle, for example, should only need to be applied to 1 face at the part level. After doing this, you will get 1 (and only 1) extra Visualize part after import...which is expected.
Again, none of this is to say we shouldn't try to handle merging things on import better and that's something we'll do. But even if we can improve this, I'd still emphatically recommend you continue the practice of applying decals to FACES of parts. Not features, bodies or components in assemblies.
Hope this helps.
Cylindrical mapped decal applied to entire body of part:
Cylindrical mapped decal applied to one face of part: