No this is to be expected. Modern Operating Systems use so called virtual memory, which only get's mapped onto physical memory when it is used.
On Unix systems you can easiely see virtual and physical memory usege. For example:
program Test;
begin
GetMem(1024*1024*1024); // Alloc 1 Gig
ReadLn; // avoid closing
end.
Compiling and executing and looking into top:
Tasks: 10 total, 1 running, 8 sleeping, 1 stopped, 0 zombie
%Cpu(s): 0.0 us, 0.3 sy, 0.0 ni, 99.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 15941.52+total, 15191.93+free, 694.270 used, 313.387 buff/cache
MiB Swap: 4096.000 total, 4096.000 free, 0.000 used. 15247.25+avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
...
345 frederic 20 0 1048988 4 0 T 0.000 0.000 0:00.00 test
...
As you can see, the process test takes about 1 gig of virtual memory (VIRT), but only 4 Kbytes of phsyical memory (RES)
If we now touch this memory once:
program Test;
var
p: PInteger;
begin
p := GetMem(1024*1024*1024);
FillChar(p^, 1024*1024*1024, #00);
ReadLn;
end.
We get in top:
top - 14:45:27 up 5 min, 0 users, load average: 0.02, 0.01, 0.00
Tasks: 11 total, 2 running, 8 sleeping, 1 stopped, 0 zombie
%Cpu(s): 0.6 us, 3.6 sy, 0.0 ni, 95.9 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 15941.52+total, 14512.57+free, 1284.270 used, 405.113 buff/cache
MiB Swap: 4096.000 total, 4096.000 free, 0.000 used. 14657.25+avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
544 frederic 20 0 1048988 578216 172 R 86.67 3.542 0:00.13 test
Which no has a massive physical memory usage (it's not quite the virutal one because operating systems are complicated).
This is actually quite adventaguous for development, because this means that (virtual) memory is free, and you can allocate as much as you want, and it will only be physically allocated when you use it.
This allows you to do things like when creating a list, pre-allocate all the memory you could possibly need (e.g. a gigabyte of data), and then fill that list. The memory will only be used as much as you filled the list.
This can be quite advantaguous for example for gemoetricly growing datastructures or things like that.