Sure, you could have spent more, or less. That's the case with every dollar you spend. I don't see what a budget changes about that.
The difference with the budget was that we knew how much we had to spend. If we hadn't decided ahead of time how much we wanted to spend on that party, we would have bought exactly what we wanted in each area rather than making trade-offs.
A budget is just the on-the-ground tactical plan for achieving your strategic goals. I can juggle a lot of competing priorities in my head, but even I have a limit. So when I'm choosing a Tequila, I'm weighing the amount and the quality and how many people are coming and whether I want better tequila or better balloons or extra guacamole, and whether I want white or gold, and whether I want to try something new or go with an old stand-by...etc. I don't want to convolute the decision with whether this purchase will leave me with enough funds to meet my goals, or if I will have enough for groceries, or blah blah blah. I just want to know "I have $X available to party with. What's the most fun I can have with my $X?" having already decided ahead of time that I could spend $X while still meeting my goals.
This is a great example. I wouldn't. So I budget $0 for clothes. But the next month I need $75 worth. No budget? Great, go buy. With my $0 budget? $&*^. If I up it to $75 in my budget, then the next month, I don't need any? Or another $100 worth.
But what if you don't actually
need $75 worth of clothes, but you want them? And you don't
need 20lbs of ground beef, but there is a decent sale and you want to take advantage of it? And you don't
need a nice bottle of wine to celebrate your anniversary, but you want it? And you don't
need an 85% savings rate this month rather than 75%, but you want it? You can't have them all - so do you just go with whichever one comes up first?
I'll tell you how it would go for us, and maybe that will help: When we set up our budget for May we knew we would have a party and an anniversary. We also knew summer was coming, and DH wanted to update his wardrobe because he has lost some weight and his old shorts don't fit as well as he would like (a want, not a need). So, we budgeted less for Groceries, knowing we could eat more rice/beans from the cupboard this month plus party leftovers. We did that so we could budget more for Clothing and for the Party and anniversary. Now, let's say hypothetically that tomorrow I find out about a great sale on beef. We would need to ask ourselves if we want to forgo the anniversary celebration and/or the new clothes to take advantage of the sale. Maybe it's a really great sale and it's worth giving up the other things to stock up. Maybe it's just a decent sale, so we just cut the other categories back a bit.
So, if we didn't budget, what would that look like? Well, I probably would have gone out and done regular grocery shopping, not realizing Hubby wanted extra money for new clothes. Then we would have spent the party money. Then the sale on beef comes up and we throw the rest of our available cash at it to stock up (seems like a good idea). Now we're out of money for our anniversary, and for Hubby's new clothes. Or, we take money that would otherwise have gone to savings to pay for those things.
You might already be doing that sort of thing in a less structured way. And I hope it would go without saying, but I don't think you *have* to budget (just like I don't track my calories). I'm just explaining why we do.