This is an attempt at only having a single type of sign, and saving the few dollars they would need to spend on a van sign. My thinking is that the sign is not restrictive, it doesn't say "no cars". But just because it it is informative, that doesn't mean it shouldn't be there to inform. The ANSI standard has no permissions for this "universal space" to not have a van sign. It does say that signs that mark van spaces shall have a sign that that says "van accessible". I think the ANSI standard intends that at least the required number of van spaces be marked for vans. This project is well over 10 million dollars, I can sleep if I ask for a couple extra bucks to "inform" the drivers. The facility has two lots, each are provided with the required number of accessible spaces. Only one van space would be required for the total number. Worst case is that they use some sense and provide one van space in each lot. They would have to pay for two small signs.
From the ADAAG annex (may be an old edition, not sure if there is a newer one)
"Universal" Parking Space Design. An alternative
to the provision of a percentage of spaces with a
wide aisle, and the associated need to include
additional signage, is the use of what has been
called the "universal" parking space design.
Under this design, all accessible spaces are 132 in
(3350 mm) wide with a 60 in (1525 mm) access
aisle (see Fig. A5(b)). One advantage to this design
is that no additional signage is needed because all
spaces can accommodate a van with a
side-mounted lift or ramp. Also, there is no
competition between cars and vans for spaces
since all spaces can accommodate either.
Furthermore, the wider space permits vehicles to
park to one side or the other within the 132 in
(3350 mm) space to allow persons to exit and
enter the vehicle on either the driver or passenger
side, although, in some cases, this would require
exiting or entering without a marked access aisle.