Fascinating - I think most people have pretty similar ideas of "reasonable cost" - I'm surprised to see that estimates are really pretty similar, though of course whether or not we're willing to spend on it varies person by person. =)
Regular shirt: I'll say $20, but honestly I am a thrift store shopper, so usually $2.50. xD
Pants: $50 for a pair of pants I like (...such a rare thing!) but again, usually at thrift stores, so $5.
Shoes: Generally, my most expensive shoes are running shoes at $50-60 for a pair. For casual shoes, or occasional-use-dress shoes, I generally stick to $20-30. However, I recently discovered Sketchers Shape Ups, and if I ever had to work another job standing on my feet for long periods of time, I would spend the full $120 retail for these shoes. They were worth EVERY penny.
Haircut: $60 plus tip for a cut and color (every 3 months or so).
Massage: $0... I trade with a therapist when I want bodywork. However if I were paying, $60 for an hour, plus tip.
Nails/Pedicure: Including the tip, $20 for a mani, $45 for a pedi.
1-hour kid class: Erm.... $5-10 for a one-hour class?
Toy: I seriously have no idea... $20? But I don't like having a lot of random, miscellaneous crap lying around. =/
Monthly night out with friends/spouse: $50 for a night out with friends (although generally I'd spend much less); $100 or more for a night out with my honey (we're paying for 2 of us, after all!)
I think my price points are based on an insider's appreciation of the service industry - I believe skilled labor deserves fair pay, and I am a pretty generous tipper. I certainly could spend less on these things, I am comfortable with my expenditures. Massages I get for free, since I was previously an LMT and can leverage that knowledge for bodywork that only costs me an exchange of time. My hair is done by a friend, and while she could/would cut me a deal if I asked (or needed it), I'm happy to support her growing business. Nails I get done irregularly, but find the indulgence worthwhile when I feel like I need a little pampering. =)
Generally I am a quality-over-quantity kind of girl, and I'm willing to pay for the difference. I do most of my clothes shopping at thrift stores, where I am selective about brands and pick up quality clothing at a very low price. Shoes, I will spend what needs to be spent to get the support and durability I need for "working" shoes (like my running shoes, or like the Shape Ups when I was working standing retail over the summer), but I tend to buy cheaply for shoes I will wear infrequently (like heels) or don't require much function out of (like flip flops and casual shoes). However, I buy things like this very, very sparingly... I have probably spent $200 on clothes/shoes in 2011, and $120 of that was a pair of Shape Ups, and I have bought more clothes than normal due to needing maternity clothes! xD If I can't find what I need at thrift stores, I head to discount stores (like TJMaxx or the Zappos outlet, which I am fortunate enough to live near) and after that, to the clearance rack at retail stores. But generally speaking, I only buy what I need, and I plan ahead, watch for good deals, buy secondhand when reasonable, and buy quality brands to ensure longevity, and overall spend very little money in this area.
But I do love my "experiences" and am happy to spend money there when I want or need it. =)