WI-13/WI-34 just end WI-34 at US-10. WI-13 was rerouted WI-34 should have just changed to WI-13 not became a duplex with it.
That's far from the only unnecessary concurrency in Wisconsin - WI-47 would logically be two or three different routes, and it even ends while concurrent with WI-182, which also ends at WI-47's terminus. Either end 182 at 47 or 47 at 182; don't make a pointless concurrency.
And I'm certain there are others, too. I agree with CNGL's point that any route that ends while concurrent with another should be truncated.
Edit: And what is the exact reason for the existence of I-894 when it is in its entirety concurrent with at least two other highways? Just call it 41, people.
I know why Wis 34 was kept. It was to give a consistent number for a connection between I-39 and Wisconsin Rapids. As for Wis 182 and Wis 47, that is so they can both connect to US 51. Wis 91 is concurrent with Wis 44 so it connects Berlin with I-41. Wis 32 would qualify as an unnecessary concurrency with US 45 from Three Lakes to the Michigan Border. The only reason why it exists is because it is the 32nd Division Memorial Highway, and it was routed from one state line to another to honor the Red Arrow Division.
Could argue that the Wis 93 concurrency with US 53 is unnecessary since Wis 93 randomly ends at Wis 35.
I understand about those now - thanks. 
Although I've also noticed that WI-32 and WI-57 seem to be very buddy-buddy with each other in that they are concurrent with each other and I-43 for a stretch, and then there's the long non-highway concurrency north of there and going through Calumet County and others.
And why exactly does the I-894 designation exist when all of it is concurrent with I-41?
By state statute, Wis 32 needs to go the length of the state to honor the 32nd Red Arrow Division. Before the statute was enacted, Wis 32 ended at US 45 in Three Lakes, which would be the more logical end. Wis 32 was extended along US 45 to meet that requirement. In Howards Grove, Wis 42 and Wis 32 were swapped to the south. Wis 32 once ended in Sheboygan and Wis 42 ended in Kenosha. The switch was done so Wis 32 could run down to the Illinois state line
Until the 1980s, Wis 32 traveled along current Wis 67, US 151, County W, and County PP between Kiel and De Pere. Wis 57 was a far superior route than Wis 32 between Kiel and De Pere, so Wis 32 was turned back to Manitowoc and Brown County control north of US 151 and ran concurrent with Wis 57 between the 2 communities. Between Kiel and US 151, WISDOT felt that the road was important enough to be a state highway so Wis 67 was extended along that stretch.
I-894 was once the lone number for the entire route and is considered the bypass for I-94. I-43 was added in 1988, while I-41 was added in 2015. On the new BGS on both ends, the route is labeled as "Bypass" along with the I-894 designation to make it clear to I-94 traffic that it should follow the route to bypass Downtown Milwaukee. John Nordquist, the former mayor of Milwaukee wanted I-94 to replace I-894 years ago and extend I-794 to the Zoo Interchange so there was a proposal before I-41 was designated.