Thats the whole point 4 wheel steering is expensive, complex and higher chance of failure as a straight rear axel. Budget is key word.
Budget is definitely not a keyword when you're talking about the government...
Honestly I'm glad they run free for some years, that got them to the Moon...
For things like this the budget would be a weight budget, not a dollar budget. Weight had to be minimized everywhere possible.
This results in some odd realities.
For example, custom fabricated item from titanium (fantastically expensive) turns out to be cheaper than off the shelf similar item from aluminum or steel. Reason is launch costs, which may be $50,000 USD per pound.